Spacecraft finds evidence of vast quantities of ice on Mars

PASADENA, Calif. -- NASA's Mars Odyssey spacecraft has found evidence that vast regions of Mars may abound in water -- a discovery that bolsters the theory that life once existed on the Red Planet.

The water is believed to be ice mixed in with the dirt, dust and rock that form the top 3 feet of the planet's surface, according to initial data released Friday.

The water probably accounts for just a few percent by mass of the surface of Mars, but covers a vast area that stretches from the frozen southern polar cap northward to about 60 degrees south latitude.

"The signal we have been getting loud and clear is there is a lot of ice on Mars," said William Boynton of the University of Arizona at Tucson. He is chief scientist for the spacecraft instrument that measures the abundance of hydrogen, a likely indicator of the presence of water.

Scientists have long known that there is water on Mars. However, the suggestion that it is present in such quantities could bolster the theory that the planet could have harbored life. Water is considered a necessary ingredient for life.

The results, the first data from Odyssey, were presented at NASA's Jet Propulsion Laboratory, which manages the $300 million mission.

Odyssey, even though it is less than two weeks into a mapping mission expected to last at least 917 days, is already changing scientists' view of the planet, said R. Stephen Saunders, Odyssey project scientist for JPL.

The spacecraft is intended to map the chemical and elemental makeup of the Martian surface and hunt for water and hot springs that could indicate geothermal activity. Another instrument, designed to measure the planet's radioactive environment and the risks it may hold for any future astronauts, has malfunctioned.

However, initial data collected before the instrument ceased working suggests that en route to Mars, astronauts would be bombarded with about twice as much radiation as are the crew members orbiting the Earth aboard the international space station, said Frank Cucinotta, chief scientist for the Mars radiation experiment.